/*
* Copyright (C) 2005 Luca Veltri - University of Parma - Italy
*
* This file is part of MjSip (http://www.mjsip.org)
*
* MjSip is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MjSip is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with MjSip; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author(s):
* Luca Veltri (luca.veltri@unipr.it)
*/
package org.zoolu.tools;
/** Generic hash/message-digest algorithm.
*/
public abstract class MessageDigest
{
/** MessageDigest block update operation.
* Continues a message-digest operation,
* processing another message block, and updating the context. */
abstract public MessageDigest update(byte[] buffer, int offset, int len);
/** MessageDigest block update operation.
* Continues a message-digest operation,
* processing another message block, and updating the context. */
public MessageDigest update(String str)
{ byte[] buf=str.getBytes();
return update(buf,0,buf.length);
}
/** MessageDigest block update operation.
* Continues a message-digest operation,
* processing another message block, and updating the context. */
public MessageDigest update(byte[] buffer)
{ return update(buffer,0,buffer.length);
}
/** MessageDigest finalization. Ends a message-digest operation, writing the
* the message digest and zeroizing the context. */
abstract public byte[] doFinal();
/** Gets the MessageDigest. The same as doFinal(). */
public byte[] getDigest()
{ return doFinal();
}
/** Gets the Message Digest as string of hex values. */
public String asHex()
{ return asHex(doFinal());
}
/** Transforms an array of bytes into a string of hex values. */
public static String asHex(byte[] buf)
{ String str=new String();
for (int i=0; i<buf.length; i++)
{ str+=Integer.toHexString((buf[i]>>>4)&0x0F);
str+=Integer.toHexString(buf[i]&0x0F);
}
return str;
}
}